feat(angular): build for angular 12.0 (#23970)

angular/src/directives/control-value-accessors/boolean-value-accessor.ts

@@ -1,32 +1,30 @@
-import { Directive, ElementRef, HostListener, Injector } from '@angular/core';
+import { Directive, HostListener, ElementRef, Injector } from '@angular/core';
 import { NG_VALUE_ACCESSOR } from '@angular/forms';
 
 import { ValueAccessor, setIonicClasses } from './value-accessor';
 
 @Directive({
-  /* tslint:disable-next-line:directive-selector */
   selector: 'ion-checkbox,ion-toggle',
   providers: [
     {
       provide: NG_VALUE_ACCESSOR,
-      useExisting: BooleanValueAccessor,
-      multi: true
-    }
-  ]
+      useExisting: BooleanValueAccessorDirective,
+      multi: true,
+    },
+  ],
 })
-export class BooleanValueAccessor extends ValueAccessor {
-
+export class BooleanValueAccessorDirective extends ValueAccessor {
   constructor(injector: Injector, el: ElementRef) {
     super(injector, el);
   }
 
-  writeValue(value: any) {
+  writeValue(value: any): void {
     this.el.nativeElement.checked = this.lastValue = value == null ? false : value;
     setIonicClasses(this.el);
   }
 
   @HostListener('ionChange', ['$event.target'])
-  _handleIonChange(el: any) {
+  _handleIonChange(el: any): void {
     this.handleChangeEvent(el, el.checked);
   }
 }